ObjectiveTo determine the signal pathway of specifically expressed oncostatin M(OSM) in lens inducing retinal degeneration in transgenic mice.MethodsA sequence-truncated OSM cDNA (661 bp) of mice was linked to αA-crytallin promoter, and was micro-injected into unicellular embryo to set up the model of transgenic mice. Reversal transcription-polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of gp130/OSMRβ receptor in the retinae of OSM transgenic and non-transgenic mice. Rabbit anti-phosphorylated STAT-3 antibody was used to detect the protein expression of phosphorylated STAT-3，and mouse anti-cytochrome C antibody was used to detect the distributing of cytochrome C in retinae. ResultsExpression of gp130/OSMRβmRNA was found in retina of non-transgenic mice. At the 17.5th day in the embryonic stage, significant accumulation of the phosphorylated STAT-3 was detected in the retinal nucleolus in OSM transgenic retina. At the first day after birth, intensive staining of cytochrome C in OSM transgenic retina was found. Conclusionsspecifically expressed OSM in lens may act on gp130/OSMRβ receptor in retinae, activate STAT-3, and cause the release of cytochrome C from mitochondria, which eventually induces widespread retinal degeneration.(Chin J Ocul Fundus Dis, 2005,21:167-169)
ObjectiveTo evaluate the inhibitory effect of small interfering RNA (siRNA) targeting peroxisome-proliferator-activated receptor-γcoactivator-1α(PGC-1α) on retinal neovascularization in the mouse. MethodsEighty seven-day-old C57BL/6J mice were divided into normal group, model blank group, model control group and PGC-1αsiRNA group, twenty mice in each group. Mice in the normal group were kept in normal room air. Mice in the model blank group, model control group and PGC-1αsiRNA group were induced for retinal neovascularization by hypoxia. Liposome with PGC-1αsiRNA (1 μl) and liposome with negative control siRNA (1 μl) were injected into the vitreous in the PGC-1αsiRNA group and model control group respectively when mice were moved out to room air from the cabin (Postnatal 12). No injection were performed in the model blank group. At postnatal 17, fluorescein angiography was used to assess the vascular pattern.The proliferative neovascular response was quantified by counting the nuclei of new vessels extending from the retina into the vitreous in cross-sections. PGC-1αand vascular endothelial growth factor (VEGF) level in retina were measured by real-time polymerase chain reaction (real-time PCR) and Western blot. Inhibition efficiency of PGC-1αsiRNA on PGC-1αand VEGF was calculated. ResultsMice in the normal group showed reticular distribution of retinal blood vessels. Central nonperfused retina, neovascular tufts and fluorescein leakage were seen in the model blank group and model control group. Neovascular tuft and fluorescein leakage were decreased in the PGC-1αsiRNA group compared to the model blank group and model control group. The neovascular nuclei were increased in the model blank group and model control group compared to the normal group (P < 0.05). The neovascular nuclei were decreased in the PGC-1αsiRNA group compared to the model blank group and model control group (P < 0.05). The expression of PGC-1αmRNA and protein in retina was increased significantly in the model blank group and model control group as compared with normal group, while decreased 54% and 53% respectively in the PGC-1αsiRNA group as compared with model blank group and model control group (P < 0.05). The expression of VEGF mRNA and protein in retina was increased significantly in the model blank group and model control group as compared with normal group, while decreased significantly in the PGC-1αsiRNA group (decreased 48% and 40% respectively) as compared with model blank group and model control group (P < 0.05). ConclusionsIntravitreal injection of PGC-1αsiRNA mediated by liposome can inhibit retinal neovascularization in the mouse effectively.
Objective To study the retinal light sensitivity of central visual field in normal children. Methods The QZS-Ⅱ automated perimetry was used to assess the visual field of centro-30deg;and centro-6deg; in normal or ametropic eyes in 60 eyes of 5～9 years old children. Results The mean sensitivity(MS)was not influenced by sex,age and laterality and ametropia of the eye.The normal type of dB distribution was obviously higher than the abnormal(P＜0.01).We set normal range as 30deg;MS＞19.3 dB, 6deg;MS＞22.5 dB.The abnormality of value or distribution didnprime;t appear in the same field. Conclusions In normal children,the dB distribution of visual field was mainly of the normal type.We suggest that in evaluating function of visual filed of the children,the dB distribution of centro-30deg;and centro-6deg;field and the value of MS should be included. (Chin J Ocul Fundus Dis, 1999, 15: 137-138)
ObjectiveTo observe the role of Notch signaling pathway inhibitor in differentiation process of stem cells derived from retinal Müller cells into the ganglion cell. MethodsRetinas of Sprague Dawley rat at postnatal 10-20 days were dissociated from eye balls. The third passage of Müller cells was used in this experiment, which cultured by repeated incomplete pancreatic enzyme digestion method. The retinal Müller cells were induced in the serum-free dedifferentiation medium. The cell proliferation state was observed under an inverted microscope. The expression of the specific markers Nestin and Ki-67 of retinal stem cells was measured by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. The positive rate of nucleus was detected by Edu. The retinal stem cells was divided into Gamma secretase inhibtor-I (GSI) group and control group, the rate of ganglion cells was counted by using immunofluorescence staining. ResultsThe cell proliferation had gathered to form a sphere. Immunofluorescence staining showed that the expressions of Nestin and Ki-67 were (92.94±6.48%) and (85.96±6.04%) respectively. Edu positive rate of nucleus was (82.80±6.65)%. RT-PCR and Western blot further confirmed the high expression of Nestin and Ki-67 in the cell spheres but not in the Müller cells. The positive rate of ganglion cells were (16.98±2.87)% and (11.17±0.71)% in GSI group and control group respectively, with the significant difference (t=3.210, P=0.002). ConclusionNotch signaling pathway is an important regulatory gene in stem cells differentiated into retinal ganglion cell.